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Introduces this issue as a special issue which is a collection of articles based on invited presentations at the 41st Annual Meeting of the Division of Plasma Physics (DPP) of the American Physical Society held in Seattle, Washington, in November 1999. Details of the program which involved several papers and a mini-conferences on Turbulence in the Interstellar Medium and Solar Wind, Plasma Propulsion Physics, Dusty Plasmas, and Computational Studies of Complexity in Turbulent Plasma; Coverage of a broad variety of research in plasma physics and highlighting of areas of intense interest and investigation, such as the basic physics of waves, instabilities, turbulence and transport and the properties of non-neutral plasmas and matter under very high pressures; Details of tutorial papers and presentations which are meant to be understood by non-experts.

An analysis of x-ray data from two series of Z-pinch shots taken on the short current-risetime Saturn accelerator at Sandia National Laboratories [Proceedings of 6th International IEEE Pulsed Power Conference, Arlington, VA, edited by P. J. Turchi and B. H. Bernstein (IEEE, New York, 1987), p. 310] is presented. In one series, the array radius was held constant and the array mass was varied; in the other series, the array mass was held constant and its radius varied. In both sets of experiments, large wire-number loads (N>=93) of aluminum were used in contrast to earlier small wire-number aluminum array experiments on Saturn where N≤42. Average electron temperatures and ion densities were inferred from the data. In addition, from the measured size of the emission region of K-shell x rays and from the inferred ion density, a fraction of the total array mass that participated in the K-shell emission was inferred and found to be directly correlated to the K-shell yields that were measured. This paper also demonstrates that the yields varied as a function of array mass and radius in much closer agreement with predictions [J. Appl. Phys. 67, 1725 (1990)] than had been observed in the earlier small wire-number experiments. Thus, a serious misperception that the reason for the early disagreement was in the calculations and not in the experiments is corrected. These predictions were made using one-dimensional (1D) magnetohydrodynamics calculations. The density and temperature trends inferred from the data analysis are well-behaved and consistent with the 1D calculations. This data analysis confirms the importance of achieving uniform plasma initial conditions and implosion symmetry when comparing computer code calculations with experiment. When the wire number of an array load is increased, a more uniform shell of plasma is calculated initially as the wires explode and, as the plasma stagnates on axis, the x-ray powers and yields are found experimentally to appro... [ABSTRACT FROM AUTHOR]